6.8mm Hollow Block Loop, 13.5-Inch, Beige

This is clearly better than any of the competing products. This has a few features which differentiate it from other Prusik loops: 1. It is rated to 19kN. 2. Aramid fibers make it immune to melting. 3. Hollow construction means it relies on flattening against the line, rather than biting like a thin accessory cord Prusik. 4. Loosens more easily than thin accessory cord Prusiks. This isn't just numbers on a page either: this translates into practice. It's a pleasure to use the Hollow Block and I feel a lot safer with it than any other Prusik system I've used.

This thing is a beauty if you're looking for a perfect prusik loop for gripping rope. It works amazingly well on the 7/16" rope I use, slides fairly easily against pulley when slack, and instantly grips like a vise when under tension. Flat surface and weave serves to provide incredible grip under tension. I use it for a progress capture in a 5:1 pulley system hauling very heavy wood up a steep side of a ravine and pulled one long log until it was suspended from the anchor fairly far up a tree trunk and released the pull rope. The heavy load was held entirely by this loop with no signs of trouble. A really great product that's fantastic for what it's designed for. I found myself wanting another, perhaps the slightly longer version, as I have a round prusik with two sewn loop ends that I thought I'd use to anchor the lower pulley against the rope to the load, and though it works, it takes some doing to set the knot. While one of these grips instantly and easily.

13.5 inches 3 to 4 wraps holds anything... anything. I almost want to take it to the hardware store and test it on straight pvc pipe like the other reviewer said. Unbelievable. Also... when unloaded with the touch of a pinky it becomes unstuck.... wtf? How is that possible. Truly the best autoblock ever. Very happy purchase. *note* I use the wrap around method on my autoblock for rappelling - not the prusik knot. I find it is easier to load and unload without slipping :) Cons: Dirty ropes make it dirty fast. lol 314lb working load? but still 3147lb breaking strength. Maybe I wish it was a little higher? At 175lbs rappelling I'm not likely to come near either. Just interesting to note.A typical sling would be around 22kn or 4950lbs breaking strength

I don't know how many different prusik loops I've tried in my hunt for an autoblock that finds a balance between gripping hard when you let go and sliding freely when you move it. On my 9.8mm rope, this thing is absolute perfection. Clipped to a let loop with a compact carabiner the 13.5 inch version is the one to buy and can go around the rope either 2 or 3 times. Experimenting with it this weekend, I found that 2 wraps gave me enough friction to arrest a very quick rap with no hands, and I never had to fight with it to get it moving again. FANTASTIC.

Hollow Blocks are amazing products. They grip better and are far easier to release than cord for friction knots. I bought this to use an a rappel autoblock backup for the new AMGA-style rap setup. I was a bit worried about the 19" being too long, so I went with the shorter one. With the shorter one, I can just barely get three wraps around double ropes and still clip the too loops. With so little excess, the whole thing is a bit tough to manipulate, too. I have since ordered the 19" and will be using that for my autoblock. The set of 13.5" and 19" will be great for any situation where two friction knots are needed, though (emergency ascending, escaping the belay, etc.).

I bought 2 of these for my climbing partner and I to use as a safety when we rap down off a climb. Seems like the older we get the less we want to die. These work great. 2 wraps is all we need, they hold great. I kind of wish I had got the longer ones but the shorter are just enough.

Beautiful and perfectly functioning. I used this as a backup while repelling and it worked on a double 9.8 mm rope with only two twists though it could have fit three, though this would have been tight. It is good quality and reliable Several of the other climbers I climb with have used this and have had no problems though they have used it for years.

This bites into a rope better than either a nylon or dyneema slings. Especially since ropes are getting thinner and thinner, "bite" is a more important consideration. I climb exclusively on dyneema slings. After a conversation with a very experienced climber about the low melting point of dyneema when used as a rap backup, I bought this. I can say that it is just another level of safety, and I am glad to have it. I bought the shorter length, and it is perfect for rap backups. The only downside is that this is not full strength, and therefore not as versatile. It is small and light on your harness, but I still prefer to carry equipment with many uses. This is a specialty piece who's only purpose is friction hitches.